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bioRxiv · 10.1101/2024.07.05.602248

Draft genome of Palmaria palmata and intraspecific genetic variations in the North-East Atlantic

Abstract

The rhodophyte Palmaria palmata (L.) Weber & Mohr is one of the target species of a growing European seaweed industry due to its high content of protein and essential amino acids which makes it suitable for human food, dietary supplements, and as salmon feed. However, the lack of a published nuclear genome limits phylogenetics analyses and gene function investigations which could help the development of a breeding programme. We present the first draft genome of P. palmata that was obtained with PacBio HiFi long read sequencing with average coverage of 10x, consisting of an assembly of 1.05 Gb, N50=2.75Mb and BUSCO completeness of 72.1%. Additionally, a population study on the whole genome of 33 P. palmata individuals from across the Northern East Atlantic area found three main clusters consistent with their geographic distribution: (1) Denmark and Norway, (2) France and western Ireland, (3) Faroe Islands. All individuals from Northern Ireland share ancestry with western Ireland and Denmark, and some individuals from the Faroe Islands show admixture from Faroe, western Ireland and Northern Ireland. These results represent a fundamental step towards breeding and genetic studies to further explore the vastly unexploited economic potential of Palmaria palmata. Highlights- We report the first draft genome of Palmaria palmata, from PacBio HiFi long reads. - The size of the genome, 1.05 Gb, is among the largest so far among the Rhodophyta. - Busco completeness of 72.1% and contig N50 of 2.75 Mb indicate good quality. - The genomes of 33 more individuals from North Atlantic Europe have been sequenced. - Phylogenetic analysis found three clusters consistent with geographic distribution.

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BibTeXRIS

Rosignoli, S., Inaba, M., Schmid, M., McHale, M., Fort, A., Edwards, M. D., Mols Mortensen, A., Bartle, R., Endal, A., Baud, A., Maggs, C., Sulpice, R.. 2024-07-10. Draft genome of Palmaria palmata and intraspecific genetic variations in the North-East Atlantic. https://doi.org/10.1101/2024.07.05.602248

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